Key Laboratory for Biomass -Resource Chemistry and Environmental Biotechnology of Hubei Province, School of Resource and Environmental Sciences, Wuhan University, Wuhan, 430072, China.
Key Laboratory for Biomass -Resource Chemistry and Environmental Biotechnology of Hubei Province, School of Resource and Environmental Sciences, Wuhan University, Wuhan, 430072, China.
Chemosphere. 2020 Jun;249:126147. doi: 10.1016/j.chemosphere.2020.126147. Epub 2020 Feb 7.
Here we report a set of experiments in which water blooming cyanobacteria Microcystis aeruginosa was repeatedly exposed to erythromycin. Growth inhibition increased with increasing erythromycin concentration (1-150 μg/L) upon first exposure. Maximum inhibition rate (76.06%), occurred under 150 μg/L erythromycin. Moreover, 96-h 50% effective concentration (EC) was 22.97 μg/L, indicating that the growth of M. aeruginosa was affected by erythromycin under common environmental concentrations. Photosynthesis was hindered by chlorophyll and photosystem II limitations. Malondialdehyde, reactive oxygen species, and superoxide dismutase contents increased significantly under certain concentrations of erythromycin, but superoxide dismutase was suppressed by 150 μg/L erythromycin. Synthesis of intracellular and extracellular microcystins was promoted by 10-60 and by 20-60 μg/L erythromycin, respectively, but both were inhibited by 100-150 μg/L. Principal component analysis and Pearson's correlation revealed the accumulation of reactive oxygen species as the dominant mechanism of erythromycin toxicity to cells. M. aeruginosa repeatedly subjected to erythromycin exposure showed obvious resistance against the antibiotic, especially when treated twice with 60 μg/L erythromycin. The 96-h EC was 81.29 μg/L. As compared to the first exposure to erythromycin, photosynthetic and antioxidant activities increased, while growth inhibition and oxidation stress decreased upon multiple exposures. Production and release of microcystins were enhanced by repeated exposure to the antibiotic. Thus, erythromycin persistence in water should be examined, as repeated exposure may lead to serious environmental and human health hazards.
在这里，我们报告了一组实验，其中反复将水华蓝藻铜绿微囊藻暴露于红霉素中。首次暴露时，随着红霉素浓度（1-150μg/L）的增加，生长抑制作用增强。在 150μg/L 红霉素下，最大抑制率（76.06%）。此外，96 小时 50%有效浓度（EC）为 22.97μg/L，表明在常见环境浓度下，红霉素会影响铜绿微囊藻的生长。光合作用受到叶绿素和光系统 II 的限制。在一定浓度的红霉素下，丙二醛、活性氧和超氧化物歧化酶含量显著增加，但 150μg/L 红霉素抑制了超氧化物歧化酶。10-60μg/L 的红霉素促进了细胞内和细胞外微囊藻毒素的合成，而 20-60μg/L 的红霉素抑制了细胞内和细胞外微囊藻毒素的合成，但 100-150μg/L 的红霉素抑制了细胞内和细胞外微囊藻毒素的合成。主成分分析和 Pearson 相关性分析表明，活性氧的积累是红霉素对细胞毒性的主要机制。铜绿微囊藻反复暴露于红霉素表现出明显的抗生素抗性，尤其是当两次用 60μg/L 红霉素处理时。96 小时 EC 为 81.29μg/L。与首次暴露于红霉素相比，多次暴露后光合作用和抗氧化活性增加，而生长抑制和氧化应激降低。抗生素的重复暴露增强了微囊藻毒素的产生和释放。因此，应该检查红霉素在水中的持久性，因为重复暴露可能会导致严重的环境和人类健康危害。
